Police are looking into a series of online threats made against a Georgia textbook publisher after a parent complained that one of the books promoted Islam and polygamy.

The controversy began last week when Hal Medlin, the parent of a student at Campbell Middle School in Cobb County, Georgia, complained to the school about an assignment that he said "slanted positively" toward Islam. "Trying to relate this to school uniforms, which was the context they put it into, didn't make much sense to me," he told WSB-TV News.

From the Atlanta Journal-Constitution, the part of the assignment in question was called the "letter from Ahlima":

The assignment by a teacher at Campbell Middle School, which asked students to write on the issue of dress codes, included a fictional two-page letter ostensibly written by a 20-year-old Saudi Arabian woman. In it, the character writes approvingly of wearing the Islamic veil -- and of her fiance's multiple wives and the law of Sharia.